request_mem_region should be used with release_mem_region, not request_region.

The semantic patch that fixes this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@r2@
expression start;
@@

request_mem_region(start,...)

@b2@
expression r2.start;
@@

request_region(start,...)

@depends on !b2@
expression r2.start;
expression E;
@@

- release_region
+ release_mem_region
  (start,E)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>